In what was a sort of mate-versus-mate among two staunch Labour Party members, Mr Barker argued amalgamation would be good for the entirety of the Bay.
Mr Nash implored that as the year drew toward a referendum, people look at the "evidence", which he claimed did not support amalgamation. The debate was in the end declared an "honourable draw".
A crowd three times bigger than expectated went home happy with the outcome of the debate arguing the moot: Amalgamation, good for Napier?
Former single-term list MP Stuart Nash aspires to replace departing National MP and former Minister of Local Government Chris Tremain for Napier at this year's general election.
The Local Government Commission's proposed change to the structure of local government in Hawke's Bay involves merging the region's five councils into one and includes a layer of boards "empowered to represent distinct local communities".
Hawke's Bay Council would be a unitary authority, combining the functions of a city or district council and a regional council.
The debate was organised by photographer Shane Jeffares and held at The Photographers' Gallery, developed in the former Red Cross hall.
Napier woman Pauline Doyle, who made a submission opposing the amalgamation proposal, said the debate was "brilliant - people can now go away and talk about it".